162 
MR. GLAISHER ON THE RADIATION OF HEAT. 
Table XLIX. 
Observations connected with Snow. 
1844. Day, hour and minute. 
Reading of thermometer in air at four 
feet high protected from radiation. 
Excess of the reading of a thermometer placed in air at the height of four feet and protected from the effects of radiation, 
above that of a thermometer fully exposed to the sky, and placed 
Clouds. 
Wind 
On long grass clear of snow. 
On long grass covered by 
| snow. 
. 
| On short grass clear of snow. 
On short grass covered by 
snow. 
On surface of ground under 
| short grass clear of snow. 
On surface of ground under 
long grass clear of snow. 
One inch below surface of 
ground under grass covered 
by snow. 
On grass cleared of snow 
covered by glass free of snow 
one inch high. 
On grass clear of snow covered 
[ by white tin one inch high. 
> 
O 
c 
G 
o 
On raw wool on snow. 
On flax on snow. 
In focus of metallic reflector 
cleared of snow. 
1 Nine inches above wood 
cleared of snow. 
One foot above snow. 
Two feet above snow. 
1 On lead six inches high 
! cleared of snow. 
| On copper on snow. 
| On zinc on snow. 
On zinc on grass cleared of 
snow. 
1 On Purbeck stone cleared 
! of snow. 
On glass on snow. 
1 On glass one inch high 
i cleared of snow. 
On white tin on snow. 
| On black tin on snow. j 
Modification. 
Amount 0-10. 
High or low. i 
Direction. f 
<d 
I 
e 
■5 
c 
OD 
Feb. 
o 
o 
O 
o 
o 
o 
n 
o 
0 
o 
o 
o 
Q - 
o 
4. 15 031-6 
7-6 
5-4 
9-8 
9-8 
9-3 
1-8 
i-9 
4-8 
90 
Clear 
A 10 0 90-7 
6-5 
5-1 
8-1 
8-0 
8-7 
2-3 
27 
3-5 
7-5 
Cirro- 
9 
stratus 
5. 5 031-0 
8-0 
-20 
6-4 
-27 
1-8 
-5-5 
5 0 
7-0 
6-5 
9-9 
17 
17 
5-2 
6-8 
7-8 
7-8 
9-7 
Clear 
5 . 7 25 
29 0 
9-2 
-30 
9-6 
-2-8 
-1-8 
-5-3 
4-2 
6-8 
8-2 
9-2 
10-9 
2-0 
20 
6-2 
60 
10-4 
5-6 
7-8 
8-8 
Flying 
3 
clouds 
6. 11 033-1 
51 
M 
5-9 
2-6 
2-6 
0-1 
-1-9 
1-6 
3-6 
2-6 
7-6 
8-0 
7-6 
21 
0-9 
0-9 
5-1 
39 
3-6 
2-6 
5-6 
4-0 
5-6 
6-1 
Cirro- 
9i 
H. 
C. 
1 
stratus 
By taking the mean of the numbers in each column, the following results are obtained 
Table L. Experiments connected with Snow. 
Situation of the thermometer, its bulb, or the substance under which it was placed 
being fully exposed to the sky. 
Mean excess of the 
reading of the ther- 
mometer in air at the 
height of four feet, 
protected from 
radiation. 
Number 
of compa- 
risons. 
On long grass clear of snow 
O 
7-3 
5 
On long grass covered by snow 
— 1-3 
3 
On short grass clear of snow 
5-5 
5 
On short grass covered by snow 
— 1*0 
3 
On surface of ground under short grass clear of snow 
0-9 
3 
On surface of ground under long grass clear of snow 
0-1 
1 
One inch below surface of ground under long grass covered by snow ... 
— 4*2 
3 
On grass cleared of snow covered by glass free from snow one inch high 
2-9 
2 
On grass clear of snow covered by white tin one inch high 
3-6 
] 
On snow 
4-8 
3 
On raw wool on snow 
8-2 
5 
On flax on snow 
8'3 
5 
In focus of metallic reflector cleared of snow 
9-3 
5 
Nine inches above wood cleared of snow 
27 
1 
One foot above snow 
1-7 
5 
Two feet above snow 
1-8 
5 
On lead six inches high cleared of snow 
6-2 
1 
On copper on snow 
57 
1 
On zinc on snow 
5-0 
3 
On zinc on grass cleared of snow 
3-6 
1 
On Purbeck stone cleared of snow 
2-6 
1 
On glass on snow 
7-6 
3 
On glass one inch high cleared of snow 
5-8 
3 
On white tin on snow 
5-9 
5 
On blackened tin on snow 
8-2 
5 j 
